Elastomeric hydrocarbon polymers are known to the art but their utility has been somewhat limited in that they have reduced strength at elevated temperatures. Continued efforts have been directed toward the improvement of the physical behavior, reliability and long term storage of materials of this type. Chopped monofilaments, such as polyesters or polyimides have been incorporated to increase tensile and tear resistance. In the present method hydrocarbon elastomeric polymers were produced which have greatly improved physical properties and are useful in the chemical ordnance field.